ext4: factor out a common helper to query extent map

Factor out a new common helper ext4_map_query_blocks() from the
ext4_da_map_blocks(), it query and return the extent map status on the
inode's extent path, no logic changes.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Link: https://patch.msgid.link/20240517124005.347221-2-yi.zhang@huaweicloud.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

fs/ext4/inode.c

@@ -453,6 +453,35 @@ static void ext4_map_blocks_es_recheck(handle_t *handle,
 }
 #endif /* ES_AGGRESSIVE_TEST */
 
+static int ext4_map_query_blocks(handle_t *handle, struct inode *inode,
+				 struct ext4_map_blocks *map)
+{
+	unsigned int status;
+	int retval;
+
+	if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
+		retval = ext4_ext_map_blocks(handle, inode, map, 0);
+	else
+		retval = ext4_ind_map_blocks(handle, inode, map, 0);
+
+	if (retval <= 0)
+		return retval;
+
+	if (unlikely(retval != map->m_len)) {
+		ext4_warning(inode->i_sb,
+			     "ES len assertion failed for inode "
+			     "%lu: retval %d != map->m_len %d",
+			     inode->i_ino, retval, map->m_len);
+		WARN_ON(1);
+	}
+
+	status = map->m_flags & EXT4_MAP_UNWRITTEN ?
+			EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
+	ext4_es_insert_extent(inode, map->m_lblk, map->m_len,
+			      map->m_pblk, status);
+	return retval;
+}
+
 /*
  * The ext4_map_blocks() function tries to look up the requested blocks,
  * and returns if the blocks are already mapped.
@@ -1744,33 +1773,11 @@ static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
 	down_read(&EXT4_I(inode)->i_data_sem);
 	if (ext4_has_inline_data(inode))
 		retval = 0;
-	else if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
-		retval = ext4_ext_map_blocks(NULL, inode, map, 0);
 	else
-		retval = ext4_ind_map_blocks(NULL, inode, map, 0);
-	if (retval < 0) {
-		up_read(&EXT4_I(inode)->i_data_sem);
-		return retval;
-	}
-	if (retval > 0) {
-		unsigned int status;
-
-		if (unlikely(retval != map->m_len)) {
-			ext4_warning(inode->i_sb,
-				     "ES len assertion failed for inode "
-				     "%lu: retval %d != map->m_len %d",
-				     inode->i_ino, retval, map->m_len);
-			WARN_ON(1);
-		}
-
-		status = map->m_flags & EXT4_MAP_UNWRITTEN ?
-				EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
-		ext4_es_insert_extent(inode, map->m_lblk, map->m_len,
-				      map->m_pblk, status);
-		up_read(&EXT4_I(inode)->i_data_sem);
-		return retval;
-	}
+		retval = ext4_map_query_blocks(NULL, inode, map);
 	up_read(&EXT4_I(inode)->i_data_sem);
+	if (retval)
+		return retval;
 
 add_delayed:
 	down_write(&EXT4_I(inode)->i_data_sem);